<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .navbar{
            position: fixed;
            top: 4.4rem;
            left: 0;
            width: 100%;
            height: 4.4rem;
            border: 1px solid #ddd;
            background-color: #fff;
            z-index: 2;
            /* overflow: hidden; */
        }
        .scroll{
        height: 4.4rem;
        /* -webkit-overflow-scrolling: touch; */

        overflow-y: auto;
    }
    .nav-wrapper{
        height: 100%;
        width: 1000rem;
    }
    </style>
</head>
<body>
    <div class="navbar">
        <div class="scroll">
            <div class="nav-wrapper">
                {{ itemList }}{{ itemList }}{{ itemList }}{{ itemList }}{{ itemList }}{{ itemList }}{{ itemList }}{{ itemList }}{{ itemList }}{{ itemList }}{{ itemList }}{{ itemList }}{{ itemList }}
            </div>
        </div>
    </div>
    <script>
       function delay(ms) {
    return new Promise(resolve => setTimeout(resolve, ms));
}

async function intense(value) {
    console.log("intense(" + value + ") - This is synchronous");
    await delay(100);
    console.log("intense(" + value + ") - This is asynchronous, because it's after `await`");
}

async function test(){
    console.log("Print 1");
    intense(1);       // <== WITHOUT await
    console.log("Print 2");
    // await intense(2); // <== With await
    console.log("Print 3");
}

test(); 
    </script>
</body>
</html>